Compact camera having electrical components mounted on one mounted board

ABSTRACT

A compact camera including one mounting board to which a plurality of electronic components are mounted. A display panel, a control unit, and a land portion, located underneath input devices, are mounted on an upper surface of the mounting board. A first drive IC and a second IC are mounted on a lower surface of the mounting board. Furthermore, a low-power device, such as an autofocus device, is mounted on a lower surface of the mounting board. The autofocus device is disposed near the input devices. Therefore, an inhibiting circuit is provided which inhibits the operation of the autofocus device when the input devices receive operation input signals.

This application is a continuation of application Ser. No. 08/295,069,filed Aug. 26, 1994, which is a continuation of 08/116,972, filed Sep.7, 1993, both now abandoned.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to an internal structure of a compactcamera, and more particularly, to mounting positions of variouselectronic components on one mounting board within the compact camera.

2. Description of the Related Art

Conventional compact cameras are designed to include a variety ofelectronic components, mounted very closely within the camera. Thecamera size is reduced due to the high-density of components locatedwithin a small area. Typical elements in a camera include a photographiclens barrel, a film cartridge chamber, a film windup spool chamber, aviewfinder device, a photometric device, an autofocus device, motordrive devices, a display device, and strobes.

A plurality of mounting boards, such as flexible printed wiring boards,have been used to interconnect all of the electrical components withinthe camera body. For example, the LCD display device, providing adisplay of information to the exterior of the camera, and the motordrive device, using an IC for performing motor drive control, are notconventionally mounted on a single board. The LCD is presently mountedon the rear cover of the camera body, while the motor drive IC ispresently mounted on the front surface of the spool chamber. Using manymounting boards, however, results in an inefficient use of space, arelatively "large" compact camera, and higher manufacturing costs.

In addition, certain components inside the compact camera operate withlow power, and are therefore highly influenced by electrical noise. Forexample, autofocus devices (hereinafter "AF" devices) and autoexposuredevices (hereinafter "AE" devices) are controlled by a very low current.The electrical noise, generated either inside or outside of the camera,adversely affects the accuracy of the low-power devices.

In order to reduce the effects of noise on the AF device, for example, asignal processing circuit (i.e., an IC) is mounted as close as possibleto the AF receiving unit. If, however, the signal processing circuitcannot be mounted adjacent to the AF receiving unit, the circuit must becarefully shielded. In a relatively larger camera, there is generally noproblem with mounting the circuit close to the AF receiving unit, orproviding a shield around the circuit.

In compact cameras, however, it is difficult to maintain the same designas in larger cameras. For example, there is no space available to mountthe circuit close to the AF receiving unit due to the smaller size ofthe camera body. Moreover, if the signal processing circuit were to bemounted at a distant place, there still is not enough space to providethe necessary shielding for the circuit. Because the length of theelectrical connections between the AF receiving unit and circuit isrelatively large in a compact camera, it is more susceptible to noise.Low-power devices in conventional miniaturized cameras do not,therefore, function accurately.

A camera typically includes operating switches, such as a switch tochange over the Speedlight flash photography mode. In compact cameras,the switches are located in close proximity to the signal processingcircuit of the AF device. The operating switches themselves generateelectrical noise when operated. The operator also generates electricalnoise which is received by the AF device. Noise from the switches andthe operator cause the AF device to function erroneously.

SUMMARY OF THE INVENTION

It is therefore an object of the present invention to provide an evensmaller compact camera, which more efficiently utilizes the limitedspace within the compact camera body.

It is a further object of the present invention to provide a compactcamera which may be manufactured at a relatively low cost.

Another object of the present invention is to provide a compact camerawhich efficiently interconnects all of the electronic components.

Yet another object of the present invention is to provide a compactcamera which includes only one mounting board with which to efficientlymount and interconnect the electronic components.

Another object of the present invention is to provide a compact camerain which the electronic components are efficiently positioned in ahigh-density area within the camera body.

Still another object of the present invention is to provide a compactcamera having low-power devices which are not adversely affected byelectrical noise.

Yet a further object of the present invention is to provide a compactcamera which includes an electronic device to prevent electrical noisefrom affecting low-power devices within the camera.

A further object of the present invention is to provide a compact camerawhich includes an control unit to prevent noise from operation inputdevices positioned near low-power devices from affecting the low-powerdevices.

The above objects are achieved by providing a compact camera whichincludes one mounting board, having an upper surface and a lowersurface, and disposed inside the compact camera, near a top portion ofthe compact camera. A display panel is mounted on the upper surface ofthe mounting board. A control unit for controlling the operation of eachdevice in the camera is also mounted on the upper surface of themounting board. Furthermore, input devices and a land portion disposedunderneath the input devices are mounted on the upper surface of themounting board. A motor drive IC is mounted on the lower surface of themounting board, and an autofocus IC is mounted on the lower surface ofthe mounting board.

In the compact camera having the structure described above, a low-powerdevice is further mounted on the lower surface of the mounting board.Since the camera is compact in size, the low-power device is positionedclose to the input devices. In order to prevent the low-power devicefrom being affected by noise produced by the input devices, the compactcamera also includes an inhibiting circuit which inhibits an operationof the low-power device when the input devices receive operation inputsignals.

BRIEF DESCRIPTION OF THE DRAWINGS

These and other objects and advantages of the invention will becomeapparent and more readily appreciated from the following description ofthe preferred embodiments, taken in conjunction with the accompanyingdrawings, of which:

FIG. 1 is a cross-sectional, schematic, frontal view of a compact camerain accordance with a first embodiment of the present invention.

FIG. 2a and FIG. 2b are schematic perspective views of componentsattached to a mounting board in the compact camera according to thefirst embodiment of the present invention.

FIG. 3 is a perspective view of a compact camera in accordance with asecond embodiment of the present invention.

FIG. 4 is a cross-sectional, schematic, frontal view of the compactcamera according to the second embodiment of the present invention.

FIG. 5 is a block diagram illustrating the operation of the compactcamera according to the second embodiment of the present invention.

FIG. 6 is a flow-chart illustrating the operation of the compact cameraaccording to the second embodiment of the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

As shown in FIG. 1, a preferred embodiment of the compact camera, inaccordance with the present invention, is designated generally by thereference character 10. The compact camera 10 includes a camera body 12.Camera body 12 includes a lens barrel 14, an electric power supplybattery 16, an electric motor for forwarding film 18, a capacitor forstrobe light generation 20, a film cartridge chamber 22, and a filmwindup spool chamber 24. The camera body 12 also includes rigid mountingboard 26, to which many electrical components are mounted.

Attached to rigid mounting board 26 is a release button 28 and its landportion 30 (shown in FIGS. 2a and 2b). Elements 28 and 30, together,form a switch. Also attached to mounting board 26 are an electric motor32 for driving lens barrel 14, a motor drive IC (integrated circuit) 34,an autofocus device 36, including a light projecting block 38 and alight receiving block 40, an LCD display panel 42, a viewfinder opticalsystem 44, a CPU 46, an autofocus IC 48, and a strobe emitting unit 50.

Attached to the upper surface of the rigid mounting board 26 are releasebutton 28, land portion 30, LCD display panel 42, and CPU 46. Attachedto the lower surface of the rigid mounting board 26 are electric motor32, motor drive IC 34, autofocus device 36, including light projectingblock 38 and light receiving block 40, viewfinder optical system 44,autofocus IC 48, and strobe emitting unit 50.

Lens barrel 14 has a photographic lens optical system (not shown) in acenter portion 15 of a front surface of lens barrel 14. An automaticexposure (AE) device (not shown) is arranged on an upper side of camerabody 12. Film cartridge chamber 22 may be loaded with a film cartridge(not shown). Film windup spool chamber 24 winds up film delivered fromthe film cartridge. CPU 46 controls the operation of each cameracomponent. LCD display panel 42 displays a variety of information,including the operating control state of photographic mode settings ofthe camera, the number of film exposures, etc. Electric motor 18includes a motor drive device (not shown) to move the film betweenchamber 22 and chamber 24. Other electrical elements (not shown) may beconnected to the CPU 46 and/or the LCD display 42, and mounted onmounting board 26.

The mounting board 26 is located on an internal wall surface on theupper side of camera body 12. Located on the lower side of camera body12 are the film windup spool chamber 24, capacitor 20, electric motor18, electric power supply battery 16, lens barrel 14, and film cartridgechamber 22. FIG. 1 illustrates that film windup spool chamber 24 islocated to the right of capacitor 20. Electric motor 18 is also locatedto the right of capacitor 20. Between the spool chamber 24 and filmcartridge chamber 22 are both the battery 16 and lens barrel 14. Thebattery 16 rests on the lower most side of camera body 12, with lensbarrel 14 above it. Capacitor 20 is located parallel to, and laterallyof, spool chamber 24.

Release button 28 projects from the top side of the camera body 12.Release switch land portion 30 is formed beneath the release button 28,which is illustrated in FIGS. 2a and 2b. Furthermore, an additional landportion, (not shown) corresponding to other external input operatingswitches (see FIGS. 3 and 4), is also arranged on the upper surface ofmounting board 26. The other operating switches are locatedcorrespondingly to the additional land portion on the upper surface ofmounting board 26.

The viewfinder optical system 44 is located on the lower surface of themounting board 26 and between lens barrel 14 and mounting board 26. Onthe left side of optical system 44 is light projecting block 38, and onthe right side of optical system 44 is light receiving block 40. Lensbarrel electric motor 32, on the lower surface of mounting board 26, islocated upward of the spool chamber 24. Film forwarding electric motor18 is within a windup shaft of spool chamber 24. IC 34 is located on thelower surface of the mounting board 26, upward of the spool chamber 24,and between light projecting block 38 and electric motor 32. IC 48 islocated on the lower surface of mounting board 26, upward of filmcartridge chamber 22, and positioned rearward of the strobe emittingunit 50, between strobe unit 50 and light receiving block 40. Theposition of light projecting block 38 and light receiving block 40 maybe interchanged.

While this layout represents an efficient, high-density mountingarrangement, providing a compact and light camera, this particulararrangement may be suitably modified. Furthermore, the form andstructure of the internal components may be suitably altered. Forexample, mounting board 26 may be a rigid-type printed circuit board,loaded with the LCD 42 and the CPU 46.

FIG. 2a shows land portion 30, LCD display panel 42, and CPU 46 mountedon the upper surface of mounting board 26. Land portion 30 is made froma conductive material. FIG. 2b, which shows a blown-up view of landportion 30, illustrates a configuration of the conductive land portion.The conductive land portion 30 contacts a depressed release button 28,thereby forming a switch. Motor 32, IC 34, light blocks 38 and 40, IC 48and strobe 50 are on the lower surface of mounting board 26.

As shown in FIG. 3, a second embodiment of the compact camera, inaccordance with the present invention, is designated generally by thereference character 10. Since this embodiment is similar to that of FIG.1, like reference numerals represent like elements.

Reference numeral 12 corresponds to the camera body, 14 is aphotographic lens barrel located in the central portion of the camerabody 12, 52 represents AF (autofocus) ranging windows located in thecentral portion of the front surface of camera body 12, and above lensbarrel 14, 54 is the viewfinder window, and 56 is the Speedlightemitting portion. Furthermore, 58 is a LCD display window which displayseach type of camera operation and photographic information. It isarranged in the center of the top portion of camera body 12. 28 is therelease button, disposed toward one side of the top of the camera body12.

60 is a first function button, 62 is a second function button, and 64 isan electric power switch. These three buttons are arranged in a row onthe top of the camera body 12, toward an opposite side of release button28. These three buttons are operating buttons which set variousoperating modes of the camera, as well as providing other functionaloperations.

The first function button 60 may be used, for example, for setting theSpeedlight photography mode. It may be depressed a number of times toindicate various modes of Speedlight emission, including ON and OFF. Theparticular mode set is displayed through the LCD display window 58. Thesecond button 62 may be used, for example, for setting a self-timermode. It, too, is depressed a number of times to indicate various modes,including one self-timer shot, two successive self-timer shots and anOFF mode. The particular mode set is displayed through the LCD displaywindow 58. Furthermore, the electric power switch 64, when set ON,places the camera 10 in a usable state.

FIG. 4 illustrates the structure of an upper part of one side portion ofcamera body 12, according to the second embodiment, which includes theportion having the first and second function buttons 60 and 62, and thepower switch 64. 22 represents a cartridge chamber which receives a filmcartridge (not shown) and is located on one side of camera body 12(corresponding to the right-hand side of the drawing). 66 is a filmrewinding shaft, which faces the interior of cartridge chamber 22.

26 is a rigid mounting board, such as a printed circuit board, forexample. It is located along the internal wall surface of the top sideof camera body 12. CPU 46 and LCD display panel 42 are mounted on theboard 26. CPU 46 controls the operation of each component in the camera10. LCD 42 is a display panel which displays various types ofinformation, including the operating control state of each portion ofthe camera, the photographic mode which has been set, the number ofphotographs, etc. 68 represents an additional circuit element.Furthermore, a land portion (shown in FIG. 2) for use in switching ONand OFF, by means of the operation of the first and second functionbuttons 60 and 62, and the power switch 64, is formed beneath theswitches. The land portion is a conductive portion on the board. The LCD42 is arranged in a position such that it can be observed from theexterior through the LCD display window 58 in the top portion of camerabody 12.

The light projecting block 38 includes an infrared light emittingelement (IRED) 70 for use in AF ranging and printed board 72 on whichlight emitting element 70 is mounted. The IRED 70 is included in AFdevice 36 (shown in FIG. 1). The AF device functions with very lowelectric power. Furthermore, light receiving block 40 includes a lightreceiving unit (PSD) 74 for use in AF ranging and printed board 76 onwhich light receiving unit 74 is mounted. Light receiving unit 74 isincluded in the AF device 36. Light emitting unit 70 and light receivingunit 74 are located in correspondence with AF ranging windows 52 on thefront side of camera body 12, as illustrated in FIG. 3.

Light receiving unit 74, for use in AF ranging, works on a very lowcurrent supply. Therefore, it is highly influenced by electrical noise.In larger cameras, an IC 48 for AF use is mounted on printed board 76,on which light receiving unit 74 is also mounted. Their close proximitysignificantly reduces the various affects of electrical noise betweenthe signal processing unit 48 and the light receiving unit 74. In thecompact camera of the present invention, however, the viewfinder prismoptical system 44 is positioned to correspond with viewfinder window 54,located between light emitting unit 70 and light receiving unit 74.There is no space available for mounting IC 48 on the same printed board76 as light receiving unit 74. Noise from input buttons 60, 62 and 64will, therefore, affect unit 74 and IC 48, because the electricalconnections between unit 74 and IC 48 span a greater distance.

Light emitting unit 70 and light receiving unit 74, for use in AFranging, are mounted on the lower surface of board 26. In addition, IC48 for AF use, which includes a signal processing circuit for the AFdevice 36, is also mounted on the board 26, adjacent to light receivingunit 74. IC 48 is mounted on the lower surface of printed circuit board26, corresponding to the function buttons 60 and 62 and electric powerswitch 64 located on the upper surface of board 26.

As stated above, light receiving unit 74 is a circuit functioning withvery low electric power, and IC 48 is its signal processing circuit. Inthe compact camera of this embodiment of the invention, unit 74 andcircuit 48 are mounted separately from each other, and connected throughmounting board 26. Moreover, function buttons 60 and 62, and powerswitch 64 are devices receiving operation inputs from the exterior, andare positioned close to unit 74 and IC 48. When the power source switch64 is operated, no noise problem exists, because the AF device 36 is notfunctioning. However, the AF device 36 is functioning during theoperation of function buttons 60 and 62. In this case, the electricalnoise will most likely be received by light receiving unit 74. Yet, inthe compactly designed camera 10 of the preferred embodiment of theinvention, there is no space available to provide shielding for IC 48.

Because function buttons 60 and 62, and power switch 64 are positionedvery close to light receiving unit 74 and IC 48, a control circuit 78,within CPU 46 is designed to inhibit the AF device, i.e., unit 74 and IC48, from functioning when function buttons 60 and 62 are operated. Inother words, during the operation of function buttons 60 and 62, asoperational input devices, the functions of AF devices IC 48 and lightreceiving unit 74 are inhibited. This eliminates the adverse affects ofelectrical noise accompanying the operation of the input devices 60 and62. Furthermore, this design increases the number of positions for theIC signal processing circuit 48, and the operation input devices 60 and62. For example, it becomes possible to place these devices closetogether, which is desirable in a compact camera.

FIG. 5 is a block diagram, where element 80 represents all thephotographic operation mechanisms in camera 10, including the shuttermechanism, the film winding mechanism, etc. All of these mechanisms 80are controlled to be driven into prescribed states by CPU 46. CPU 46includes control circuit 78. Release button 28 (including switches SW1,SW2) is used to control CPU 46. When function buttons 60 and 62,however, are operated during a photographic operation, the function oflow-power devices, such as AF devices 74 and 48, are suspended bycontrol circuit 78.

FIG. 6 is a flow chart of part of the operation of camera 10. Camera 10is set for photographic operation at the START position. In step S1 therelease button 28 is half pressed, corresponding to switch SW1, and itis confirmed that the switch SW1 has been set ON. If the SW1 is not setON, release button 28 is half-pressed again in step S1. If SW1 is ON,step S2 occurs. In step S2, it is detected whether or not the functionbuttons 60 and 62 are in the ON state. When the modes switches 60 and 62are in the OFF state, step S3 occurs. In step S3, the AF function isperformed. However, when the mode switches are ON in step S2, the AFfunction, which is in a state likely to be influenced by electricalnoise, is temporarily inhibited, and this routine is repeated startingat step S1. Furthermore, when the AF function ends in step S3, step S4occurs. In step S4, the release button 28 is fully pressed,corresponding to switch SW2, and if SW2 is set ON, step S5 occurs. Instep S5, the release operation is performed and normal photographicoperation begins. If SW2 is not set ON in step S4, the routine isrepeated, starting at step S1.

The second embodiment of the invention is not limited to the structuredisclosed above. The form and structure of each portion of camera 10 canbe suitably modified or altered. Further, the application of the secondembodiment is not limited to AF devices, such as devices functioningwith very low power, but can also be applied to photometric elements(i.e., AE devices) and the like, having very low current signalcircuits. Also, the inhibiting control circuit, applied to a deviceusing very low electric current, in an electronic instrument equippedwith operation input function buttons, may be applied to variouselectric instruments, in addition to a compact camera.

Although the above preferred embodiments of the invention have beenshown and described, it will be appreciated by those skilled in the artthat changes may be made in these embodiments, without departing fromthe principles and the spirit of the invention, the scope of which isdefined in the appended claims and their equivalents.

What is claimed is:
 1. A compact camera, including a plurality ofcomponents, comprising:one mounting board, having an upper surface and alower surface, disposed inside the compact camera and near a top portionof the compact camera; a display panel mounted on said upper surface ofsaid mounting board; a controller which controls the operation of saidplurality of components in the compact camera, mounted on said uppersurface of said mounting board; a land portion, disposed underneath atleast one input device, and mounted on said upper surface of saidmounting board; a first IC mounted on said lower surface of saidmounting board; and a second IC mounted on said lower surface of saidmounting board.
 2. The compact camera as claimed in claim 1 furthercomprising:a lens barrel, having a photographic optical system, anddisposed between a film cartridge chamber and a film windup spoolchamber; a first electric motor which drives said lens barrel, mountedon said lower surface of said mounting board and between said mountingboard and said film windup spool chamber; a second electric motor whichtransports film between said film cartridge chamber and said film windupspool chamber; an autofocus device, including a light projection unitand a light receiving unit, mounted on said lower surface of saidmounting board; a viewfinder optical system disposed between said lightprojecting unit and said light receiving unit and mounted on said lowersurface of said mounting board; and a strobe light emission devicemounted on said lower surface of said mounting board, and wherein saidfirst IC is disposed between said first electric motor and saidautofocus device, said second IC is disposed between said strobe lightemission device and said autofocus device, and said second IC isdisposed between said mounting board and said film cartridge chamber. 3.The compact camera as claimed in claim 1, wherein said mounting board isa rigid printed circuit board.
 4. The compact camera as claimed in claim1, further comprising:a low-power device functioning with a low level ofpower and disposed near said at least one input device; and inhibitingmeans for inhibiting an operation of said low-power device when said atleast one input device receives an operation input signal.
 5. Thecompact camera as claimed in claim 4, wherein said control meansincludes said inhibiting means.
 6. The compact camera as claimed inclaim 4, wherein said low-power device is an autofocus device and ismounted on said lower surface of said mounting board.
 7. The compactcamera as claimed in claim 2, wherein said autofocus device operateswith a low level of power and said compact camera further comprisesinhibiting means for inhibiting an operation of said autofocus devicewhen said at least one input device receives an operation input signal.8. A compact camera, including a plurality of components, comprising:amounting board, having an upper surface and a lower surface, disposedinside the compact camera and near a top portion of the compact camera;a display panel mounted on said upper surface of said mounting board; acontroller which controls the operation of said plurality of componentsin the compact camera, mounted on said upper surface of said mountingboard; a land portion, disposed underneath at least one input device,and mounted on said upper surface of said mounting board; a first ICmounted under said mounting board; and a second IC mounted under saidmounting board.